Control circuitry for remote tuning system

ABSTRACT

In a signal receiver having pushbuttons for tuning individual signal channels, a control circuit for a remote tuning system includes a bi-directional motor coupled to first and second potential development means each responsive to opposite directional rotation signals and to a rotary switching means for selectively coupling a potential source to a selected channel contact in accordance with the selected rotational direction signal. A potential sustaining means couples the rotary switching means to the first and second potential development means and insures continued rotation of the rotary switching means intermediate the signal channel contacts.

United States Patent 1 [111 3,801,897 LeFevre Apr. 2, 1974 [54] CONTROLCIRCUITRY FOR REMOTE 3,266,021 8/1966 Druz cl al. 334/8 X TUNING T M3,573,684 4/l97l Dickinson 334/8 [75] Inventor: gag] Eshelman LeFevre,Pavilion, Primary Examiner Archie R. Borchelt AssistantExaminer-Saxfield Chatmon, Jr. [73] Assignee: GTE SylvanniaIncorporated, Attorney, Agent, or FirmNorman J. OMalley;

Seneca Falls, N.Y. Thomas H. Buffton; Cyril A. Krenzer [22] Filed: Jan.26, 1973 21 Appl. No.: 326,828 [57] ABSTRACT In a signal receiver havingpushbuttons for tuning individual signal channels, a control circuit fora remote [52] US. Cl 334/8?:2353 ;/9l20,33;54/11656, tuning Systemincludes a bidirectional motor coupled 51 I t Cl to first and secondpotential development means each d 52% responsive to oppositedirectional rotation signals and 1 le 0 l g to a rotary switching meansfor selectively coupling a l potential source to a selected channelcontact in ac- 5 6 R f d cordance with the selected rotational directionsignal. 1 e erences A potential sustaining means couples the rotaryUNITED STATES PATENTS switching means to the first and second potentialde- 2,888,625 5/1959 Farrell et al. 334/9 X velopment means and insurescontinued rotation of 3,116,454 12/1963 Morris 3 /9 X the rotaryswitching means intermediate the signal Travis Ct 31. X channel contacts3,325,593 6/1967 Platt et al. 334/8 X 3,044,0l6 7/1962 Frihart et al334/10 X 16 Claims, 3 Drawing Figures 8+ Q VAC 3*- 35 illi WE JPATENTEDAPR 2 1974 SHEET 3 BF 3 CONTROL CIRCUITRY FOR REMOTE TUNINGSYSTEM CROSS-REFERENCE TO OTHER APPLICATIONS An application entitledPushbutton Tuning System filed concurrently herewith in the names ofWilliam Lee Arrington and Lee Irving Merz, application Ser. No. 326,759,relates to a pushbutton type signal channel selector. An applicationentitled Varactor Tuner Band Switching Circuitry filed concurrentlyherewith in the name of the inventor of the present application andapplication Ser. No. 326,758 relates to bandswitching apparatus suitablefor use with the apparatus of the present application. Also, anapplication entitled Varactor Tuner Band Switching and Signal IndicatingCircuitry filed concurrently herewith in the name of the inventor of thepresent application and application Ser. No. 326,829 relates to acombined band switching and signal indicating circuit suitable for usewith the present apparatus.

BACKGROUND OF THE INVENTION The invention relates to control circuitryfor a remote tuning system in a signal receiver. A bidirectional motorresponds to first and second transmitted signals to effect directionalrotation of a rotary switching means and selection of a desired signalchannel. I

Generally, remote control systems of the wireless type include anultrasonic tone transmitter which provides a pair of signals atdiffering signal frequencies. A receiver includes detection apparatusfor providing a pair of signals which control a bi-directional motor.Thus, one signal from the tone transmitter causes advancement of theremotely driven tuner in one rotational direction while the other signalcauses an opposite rotation of the remotely driven tuner.

Although the above-mentioned technique was satisfactory for years, theadvent of compatible tuning for UHF and VHF signal bands has presentednumerous problems, and particularly with respect to remote tuningsystems. For example, UHF and VHF tuning. must be substantially similarwhich would necessitate additional signals for controlling'the UHFsignal band in the same manner as the VHF signal band. Moreover, controlsignal frequencies are typically selected from a range between thesecond and third harmonics of the 15,750 kHz horizontal oscillatorfrequency and this range of frequenciesis severely restricted.

As a result of the requirement for compatible UHF and VHF tuning and thelimited range of available signals within a frequency range desirablefor effecting remote control of signal channel selection, there has beena trend toward varactor or varicap tuners and a multiple pushbuttontechnique. Thus, a separate pushbutton is employed for. each signalchannel'and each signal channel provides a distinct potential wherebythe varactor tuner selects a given tuning frequency. Moreover, a remotecontrol system must respond to external signals in a manner such that aresult is obtained which duplicates or corresponds to the ordinarymanual signal channel selection capability.

One known technique for remotely controlling a multiple pushbutton typetuning apparatus includes a printed circuit switching means having amultitude of diodes and transistors. Obviously,,such an elaborate systemis not only costly but also is most difficult to service. Moreover, thesystem leaves much to be desired with respect to manual response time aswell as reliability and dependability of components.

OBJECTS AND SUMMARY OF THE INVENTION Therefore, it is an object of thepresent invention to provide an enhanced control circuit for a remotecontrol system of a signal receiver. Another object of the invention isto provide an improved control circuit for sustaining directionalrotation of a remote control system intermediate signal channelselection. Still another object of the invention is to provide anenhanced bidirectional control circuit for improved operation of aremote control system utilized in a signal receiver having a pluralityof signal channels. A further object of the invention is to provideimproved control circuitry for a remote control system wherein trackingof manual tuning by the remote tuning apparatus is effected.

These and other objects, advantages and capabilities are achieved in oneaspect of the invention by a control circuit for a remote control systemwherein a bidirectional motor coupled to first and second potentialdevelopment means responsive to opposing rotational direction signals iscoupled to a rotary switching means for applying a potential to a signalchannel and to a sustaining circuit for continuing the directionalrotation of the bi-directional motor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is ablock diagram of a controlcircuit for a remote control system utilized in a signal receiver havinga plurality of signal channels;

FIG. 2 is a schematic illustration of a specific bidirectional controlcircuit for a remote control system wherein an AC motor is utilized; and

FIG. 3 is a schematic illustration of a control circuit for a remotecontrol system wherein a DC motor is employed to provide bi-directionalrotation of a signal channel selector.

DESCRIPTION OF THE PREFERRED EMBODIMENTS For a better understanding ofthe present invention, together with other and further objects,advantages and capabilities thereof, reference is made to the followingdisclosure and appended claims in conjunction with the accompanyingdrawings.

In the drawings, FIG. 1 is a schematic illustration, in block form, of acontrol circuit for a remote control system of a signal receiver havinga plurality of pushbutton controlled signal channels. Herein, first andsecond potential development means 7 and 9 are each coupled to a signalsource 10 of a different frequency and to a bi-directional motor 11.Also, each one of the firstand second potential development means 7 and9 is coupled to a potential source B+ and a potential reference levelsuch as circuit ground. Moreover, each of the first'and second'potential development means 7 and 9 includes detector and amplifiercircuitry 13 as well as switching means 15 for effecting development ofa control potential in response to a received signal.

A rotary switching means 17 having a plurality of individual signalchannel contacts'and a rotatable arm member is mechanically coupled tothe bi-directional motor 11. The rotary switching means 17 isselectively coupled to a potential source 19 by a remote-manualswitching means 21. Also, therotary switching means 17 is coupled to apotential sustaining means 23 which is, in turn, coupled to the firstand second potential development means 7 and 9. Moreover, theremotemanual switching means 21 includes a remote solenoid means 22which is coupled and responsive to the first and second potentialdevelopment means 7 and 9.

Additionally, a disablement circuit 25 interconnects the first andsecond potential development means 7 and 9 to effect inoperation of oneduring operation of the other. Also, a tracking means 27 couples thejunction of the remote-manual switching means 21 and rotary switchingmeans 17 to the potential sustaining means 23.

As to operation, a remote tone transmitter provides a signal of a givenfrequency at the signal source 10 and this signal is applied to andactivates one of the first or second signal potential development means7 or 9. Therein, a signal representative of a given direction ofrotation causes development of a potential which is applied to thebi-directional motor means 1 l to effect rotation in a desireddirection. At the same time, a potential from one of the first andsecond signal potential development means 7 or 9 is applied to theremotemanual switching means 21 to effect coupling of the power source19 to the rotary switching means 17 which includes a rotatable arm and aplurality of signal channel contacts.

As the bi-direction motor means 11 moves in a given rotationaldirection, the rotatable arm of the rotary switching means 17, which ismechanically coupled to the motor means 11, advances from one signalchannel contact toward another.

During the period when the rotatable arm is advancing from one signalchannel contact toward another, the signal applied to the potentialdevelopment means 7 or 9 may cease leaving the rotatable arm betweencontacts whereupon the potential from the power source 19 is no longeravailable to the bi-directional motor means 11. Thereupon, the potentialsustaining means 23 alters the operation of one of the potentialdeveloping means 7 or 9 in a manner such that the initiated directionalrotation of the bi-directional motor means 11 is maintained. Thus, therotational arm advances to a following signal channel contact. In thismanner, a signal from a remote tone generator initiates rotationalmovement of the motor means 11 and the sustaining circuitry means 23maintains the initiated rotational movement until a following signalchannel contact is reached by the rotatable arm of the rotary switchingmeans 17.

Also, the disablement circuitry 25 responds to activation of one of thefirst and second potential development means 7 or 9 to render the otherone of the first and second potential development means 7 or 9inoperative. In other words, activation of one potential developmentmeans 7 to effect rotation of the motor means 11 in one direction isaccompanied by inactivation of the other potential development means 9for effecting an opposite rotational direction of the motor means 1 1.

Further, tracking of manual tuning by a remote tuning circuit involvesapplication of a potential from the potential source 19 via theremote-manual switching means 21 and rotary switching means 17 to thetracking circuitry 27. However, manual selection of another signalchannel interrupts the above-mentioned potential from the potentialsource 19 whereupon the tracking circuitry 27 and sustaining circuitry23 provides a potential which continues to energize one of the potentialdevelopment means 7 or 9, which in turn, energizes the bi-directionalmotor means 11. Thereupon, the rotatable arm of the rotary switchingmeans 17 is moved until contact with the manually selected signalchannel contact by the rotatable arm is effected. Thus, manual signalchannel selection is accompanied by automatic remote signal channeltracking and a remote system tracks or follows manual signal channelselection to eliminate undesired confusion when remote control is againutilized.

In a preferred embodiment, FIG. 2 illustrates a control circuit for aremote control system wherein an AC motor is utilized. Herein, first andsecond potential development means 31 and 33 are each connected to asignal source 32 and 34, and to a potential source B+ (forbi-directional control of an AC bi-directional motor means 35.) Thebi-directional motor means 35 is mechanically coupled to a rotaryswitching means 37 which is, in turn, electrically connected to apotential source 39 by a remote-manual switching means 41.

The rotary switching means 37 is coupled to a potential sustaining means43 which is, in turn, coupled to the first and second potential,development means 31 and 33. A tracking circuit 45 couples the junctionof the rotary switching means 37 and the remote-manual switching means41 to the potential sustaining means 43. Also, the remote-manualswitching means 41 is coupled to the first and second potentialdevelopment means 31 and 33.

More specifically, each of the first and second potential developmentmeans 31 and 33 includes a diode 47 and 48, amplifier stage 49 and 50,and switching stage 51 and 52. The diodes 47 and 48 are coupled to thesignal source 32 and 34 and to the base of the amplifier stages 49 and50 while the collectors of the amplifier stages 49 and 50 are coupled toa potential source B+ via the winding coils of relays 53 and 54 coupledto the AC motor means 35. The collector of each of the amplifier stages49 and 50 is also coupled to the base of the opposite switching stage 52and 51 of the potential development means 33 and .31 by first resistors55 and 56 and to circuit ground respectively by series connected secondresistors 57 and 58. Also, the emitter of the amplifier stages 49 and 50of each of the first and second potential development means 31 and 33 iscoupled to the collector of the switching stages 51 and 52 respectivelywhich have an emitter coupled to circuit ground.

The bi-directional AC motor means 35 is mechanically coupled to arotatable arm 59 of the rotary switching means 37. The rotatable arm 59is coupled to a first terminal 61 of the remote-manual switching means41 and selectively connectable to each one of a plurality of signalchannel contacts 63. All of the signal channel contacts 63 are connectedto a second terminal 65 of the remote-manual switching means 41 bymanually operable switches 67 with the first and second terminals 61 and65 of the remote manual switching means 41 selectively coupled by aresistor 66 to the potential source 39.

Each one of the signal channel contacts 63 is directly coupled to a neonlamp 68. The manually operable switches 67 are mechanicallyinterconnected to render only a single switch operative at any one timeas set forth in the above-mentioned Pushbutton Tuning System. The neonlamps 68 are collectively coupled in band switching groups by way of apair of transistors, 69 and 71, to VHF and UHF varistor or varicaptuners, 72 and 74, and by way of a pair of diodes, 73 and 75, to thepotential sustaining means 43.

The potential sustaining means 43 includes a transistor 77 having a baseelectrode coupled by series connected resistors 79 and 80 to a potentialsource 3+ and by the series connected resistor 79, diode 81, andresistor 83 to circuit ground. The junction of the series connecteddiode 81 and resistor 83 is coupled to the diodes 73 and 75 of therotary switching means 37. The emitter electrode of the transistor 77 iscoupled to circuit ground while the collector electrode is coupled tothe potential source B+ by a resistor 87 and to the junction 89 of apair of back-to-back diodes 91 and 93. Each of the diodes 91 and 93 isconnected by a resistor, 95 and 97 respectively, to the junction of thediodes 47 and 48 and base electrode of the amplifier transistors 49 and50 in each of the first and second potential development means 31 and33.

Additionally, a tracking circuit 45 includes a series connected diode 99and resistor 101 with a resistor 102 coupling the junction thereof tocircuit ground. This tracking circuit 45 is coupled intermediate thejunction of the rotatable arm 59 of the rotary switching means 37 andthe first terminal 61 of the remote-manual switching means 41 and thejunction of the series connected resistor 80 and diode 81 of thepotential sustaining means 43. Moreover, the remote-manual switchingmeans 41 includes a relay means 103 coupled to the junction of therelays 53 and 54 which control the bidirectional motor means 35 and thefirst and second potential development means 31 and 33.

As to an example of operation, the bi-directional AC motor 35 rotatesclockwise upon energization of the first potential development means 31and counterclockwise upon energization of the second potentialdevelopment means 33. When neither of the potential development means 31or 33 is energized, the motor 35 does not rotate.

An amplified remote signal of a given frequency applied to the signalsource 32 causes current to flow through the diode 47 of the firstpotential development means 31. Thereupon, current flows through thebaseemitter junction of the amplifier stage 49, and collector-emitterjunction of the switching stage 51 to circuit ground. Current flowingthrough the base-emitter junction of the amplifier stage 49 causescurrent flow from the potential source 13+, through the coil winding ofthe control relay 53, through the collector-emitter junction ofamplifier 49 and the collectoremitter junction of the switching means 51to circuit ground. Therefore, the motor means 35 rotates in a clockwisedirection.

When the motor means 35 rotates, the shaft thereof is mechanicallycoupled to the rotatable arm 59 of the rotary switching means 37whereupon the rotatable arm 59 advances from one toward another of thesignal channel contacts 63. As the rotatablearm 59 leaves one of thesignal channel contacts 63 to advance to another, base-emitter currentto the transistors 69 and 71 supplied from the potential source 39 viathe resistor 66, remote-manual switch means 41, rotatable arm 59, andneon bulb 68 is interrupted. Moreover, the current for the VHF and UHFtuners 72 and 74, which is supplied through the collector-emitterjunctions of the transistors 69 and 71 from the source B+, is alsointerrupted whereupon the potential 13+ does not appear at the VHF andUHF tuners 72 and 74 not at the cathode of the diode 81 of the potentialsustaining means 43.

With the removal of the potential B+ from the cathode of the diode 81,the diode 81 is no longer back biased and conducts current supplied bythe potential source B+ via the resistors 80, and 83 to circuit ground.Since the diode 81 is conducting, the current from the potential sourceB+ which would otherwise flow through the resistors 80 and 79 and thebaseemitter junction of the transistor 77 flows through the diode 81whereupon the transistor 77 is nonconducting. With the transistor 77turned off, current from the potential source B+ will flow through theresistor 87, diode 91, resistor 95, base-emitter junction of theamplifier transistor 49, and collector-emitter junction of the switchingtransistor 51 to circuit ground. Thus, base-emitter current flow in theamplifier transistor stage 49 which was initiated by a remote signal byway of the signal source 32 and diode 47 is no longer dependent-upon theinitiating remote signal.

Rather, the potential sustaining means 43 assures that the motor means35 will continue to drive the rotatable arm 59 of the rotary switchingmeans 37 until a succeeding signal channel contact 63 is attained.

Thereupon, base-current flow in the transistors 69 or 71 will bereinstated due to the potentials applied thereto from the potentialsource 3+ and the potential source 39 via the resistor 66, remote-manualswitching means 41, and rotatable arm 59. Moreover, the abovementionedpotential available through the diodes 73 and will once again back biasthe diode 81 of the potential sustaining means 43 rendering the diode 81nonconductive.

With the diode 81 non-conductive, current will now flow from thepotential source B+ through the resistors and 79 and and thebase-emitter junction of the transistor 77 to circuit ground. Thecollector-emitter current of the transistor 77 will flow from thepotential source B+ through the resistor 87 and transistor 77 to circuitground. This current flow renders the collector electrode of thetransistor 77 at a potential substantially at or near circuit groundpotential whereupon current flow through the diode 91 will essentiallycease. Since the remote signal has been removed and current flow throughthe diode 91 has ceased, the transistor amplifier 49 is turned offwhich, in turn, interrupts current flow through the winding of relay 53whereupon the bi-directional motor 35 ceases to rotate.

Further, continued rotation of the rotatable arm 59 in the initiateddirection is assured by a disablement circuit arrangement wherebyenergizing current for the winding of the relay 53 coupled to the firstpotential development means 31 must pass through the collectoremitterjunction of the switch transistor 51. Energizing current for the windingof the relay 54 coupled to the second potential development means 33must pass through the collector-emitter junction of the switchtransistor 52 of the second potential development means 33.

The base-emitter current for the switch transistor 52 of the secondpotential development means 33 is supplied from the potential source B+via the coil winding of the relay 53 coupled to the first potentialdevelopment means 31 and the resistor 55 coupled to the base electrodeof the switch transistor 52 of the second potential development means33. When the transistor amplifier 49 of the first potential developmentmeans 31 is turned on, the collector voltage drops to a value low enoughto prevent current flow through the resistor 55 and the base-emitterjunction of the switching transistor 52 of the second potentialdevelopment means 33. Thus, the switching transistor 52 is turned off.

The potential appearing at the diode 91 which assures continued rotationof the motor means 35 in the initial direction also appears at the diode93. However, the current path through the diode 93 and through thebase-emitter junction of the amplifier 50 of the second potentialdevelopment means 33 is broken at the collector-emitter junction of theswitching transistor 52 which is in a non-conductive state. Thus,continued rotation in the desired direction is assured.

When the rotatable arm 59 of the rotary switching means 37 reachesanother signal channel contact 63, the potential applied to the VHF orUHF tuners 72 and 74 from the potential source 39 is restored. Also, theamplifier stages 49 and 50 of each one of the first and second potentialdevelopment means 31 and 33 are turned off while the switchingtransistors 51 and 52 of each of the potential development means 31 and33 are turned on due to the current flow through the coil winding relays53 and 54 and resistors 55 and 56. However, current flow through thecoil windings of the relays 53 and 54 is insufficient to energize therelays 53 and 54 but renders the system receptive to initiation ineither rotational direction.

Further, rotation in a counterclockwise direction of the motor means 35and rotatable arm 59 to effect a signal channel selection is initiatedand continued in a manner substantially as described above. However, theamplified remote signal is applied from the signal source 34 causingcurrent flow through the diode 48 and the base-emitter junction of theamplifier transistor 50 of the second potential development means 33.The operation is similar to clockwise rotation except for thesubstitution of the coil winding relay 54 for the coil winding relay 53of the motor means 35, transistor 50 for transistor 49, switchtransistor 52 for switch transistor 51, resistor 56 for resistor 55 anddiode 93 for diode 91.

Additionally, the tracking means 45 provides tracking of manual tuningby a remote tuning circuit. Herein, manual signal channel selection iseffected by closure of one of the manually operable switches 67 of therotary switching means 37 whereupon the remaining interconnected channelselecting switches are opened as set forth in the co-pending applicationentitled Pushbutton Tuning System.

With one of the manual switches 67 closed, current flows from thepotential source 39, through the second terminal 65 of the remote-manualswitching means 41, through the closed manual switch 67, the rotatablearm 59 of the rotary switching means 37, the resistor 101 of thetracking means 45, and to the diode 99 to effect bias biasing ornon-conduction of the diode 99. Also, current from the potential sourceB+ flows through resistors 80 and 79 and through the base-emitterjunction of the transistor 77. Thereupon, the transistor 77 is renderedconductive from emitter to collector with the collector coupled to thejunction 89 of the diodes 91 and 93 and the emitter coupled to circuitground. Thus, the junction 89 of the diodes 91 and 93 is very nearcircuit ground potential preventing current flow through the diodes 91and 93 to the amplifier stages 49 and 50. Moreover, without base-emittercurrent flow in either of the amplifier stages 49 and 50 nor in thewindings 53 and 54 the motor means 35 will not run in either directionand the rotatable arm 59 remains fixed.

However, selection of a different one of the manually operable signalchannel switches 67 opens the previously selected signal channel switch67. Thereupon, continuity from the potential source 39 to the diode 99is interrupted and the diode 99 is no longer back biased and currentflows from the potential source B+ through the resistor 80, the diode99, and resistor 102 to circuit ground. Thereupon, base-emitter currentwill no longer flow in the transistor 77 which, in turn, will no longerconduct a collector-emitter current. Thus, current will flow from thepotential source B+ through resistor 87 to the diodes 91 and 93 and tothe amplifier stages 49 and 50 to effect base-emitter current flow inone of the amplifier stages 49 or 50. By inherent imbalance due to partstolerances in the amplifier stages 49 and 50, one of the coil windingsof the relays 53 and 54 will have current flow therethrough in an amountsufficient to energize the motor means 35 which, in turn, will activatethe rotatable arm 59 until the manually selected signal channel switch67 is attained. Thus, the remote system tracks or follows the manualoperation.

Alternatively, FIG. 3 illustrates a control circuit for a remote controlsystem wherein a DC motor and circuitry are employed. Herein, first andsecond potential development means 131 and 133 are each connected to asignal source, 132 and 134 respectively, and to a potential source B+. Abi-directional DC motor means 135 is mechanically coupled to a rotaryswitching means 137. The rotary switching means 137 is coupled to apotential source 139 by way of a remote-manual switching means 141.

The rotary switching means 137 is coupled to a potential sustainingmeans 143 which is, in turn, coupled to the first and second potentialdevelopment means 131 and 133. Also, the remote-manual switching means141 includes a remote solenoid 142 which is coupled to the first andsecond potential development means 131 and 133.

Additionally, tracking means 145 couples the junction of the rotaryswitching means 137 and remotemanual switching means 141 to the junctionof the potential sustaining means 143 and the second potentialdevelopment means 133. A disablement circuit 146 interconnects the firstand second potential development means 131 and 133 whereby inoperationof one of the potential development means 131 or 133 is effected uponoperation of the other.

'More specifically, each of the first and second potential developmentmeans 131and 133 includes a detector transistor 147 and 148 having abase electrode coupled to a signal source 132 and 134, an emitterelectrode coupled to circuit ground, and a collector electrode coupledto a potential source B+ by'a resistor 149 and 150 and to a diode 151and 152. The diodes 151 and 152 are connected to the base of amplifiertransistors 153 and 154 which have a collector electrode connected by aresistor 155 and 156 to circuit ground and to the gate of a siliconcontrol rectifier (SCR) 157 and 158.

Each one of the SCR's 157 and 158 has a cathode electrode directlyconnected to circuit ground and an anode electrode coupled to circuitground by a parallel connected capacitor 159 and 160 and diode 161 and162. The anode electrodes of the SCRs 157 and 158 are interconnected bya series connected transformer winding 163 and DC motor means 164. Also,the disablement circuit 146 includes a resistor 165 coupled to circuitground by a capacitor 166 and interconnecting the anode of the SCR 157and the emitter electrode of the amplifier transistor 154 while aresistor 167 is coupled to circuit ground by a capacitor 168 andinterconnects the anode of the SCR 158 and the emitter electrode of theamplifier transistor 153.

The bi-directional DC motor 164 is mechanically coupled to the rotaryswitching means 137 and more flow through the gate electrode of the SCR157, the SCR 157 is turned on which starts the DC motor 164 and causesit to run in a given direction. Moreover, conduction of the SCR 157causes the anode electrode to approach ground potential whereupon thepotential at the emitter of the amplifier transistor 154 is removedrendering the amplifier transistor 154 non-conductive. Moreover, as therotatable arm 169 advances intermediate the signal channel contacts 171,the voltage from the potential source 139 which would cause B+ potentialto be applied to the VHF or UHF tuner 179 or 181,

is interrupted. Thereupon, the junction of the diodes specifically to arotatable arm 169. The rotatable arm 169 is electrically connected to aremote terminal 170 of the remote-manual switching means 141 and to thetracking means 145. Also, the rotatable arm 169 is selectively connectedto one of a plurality of signal channel contacts 171 each of which isconnected to a neon lamp 172. A manually operable switch 173 is coupledto the junction of each one of the signal channel contacts 171 and neonlamps 172 and connected in common to a manual terminal 174 of theremotemanual switching means 141. Moreover, the manually operableswitches 173 are mechanically interconnected to provide non-conductionof all except a selected one of the switches 173.

The neon lamps 172 are connected in parallel coupled band switchinggroups to the base of a pair of transistors 175 and 177 which areconnected to VHF and UHF varactor tuners 179 and 181 and by way of apair of diodes 183 and 185 and a resistor 187 to the potentialsustaining means 143. The potential sustaining means 143 includes aresistor 189 coupling the resistor 187 to circuit ground with a firstseries connected diode 191 and resistor 193 coupling the resistor 187 tothe base electrode of the amplifier transistor 153 and a second seriesconnected diode 195 and resistor 197' coupled to the first diode 191 andresistor 187 and to the base electrode of the amplifier transistor 154.

Further, the tracking means 145 includes a pair of resistors 199 and 201series connected intermediate the remote terminal 170 of theremote-manual switching means 141 and circuit ground. A series connecteddiode 203 and resistor 205 connects the junction of the series connectedresistors 199 and 201 to the junction of the potential sustaining means143 and second potential development means 133.

As to operation, applying a signal from a remote transmitter to thesignal source 132, for example, causes base-emitter current flow whichrenders the detector transistor 147 conductive and causes the collectorelectrode of the detector transistor 147 to assume a potential veryclose to circuit ground potential. Thereupon, the diode 151 coupled tothe collector electrode of the detector transistor 147 lowers the baseelectrode of the amplifier transistor 153 below the potential of theemitter electrode. This emitter electrode potential is supplied from thetransformer winding 163 and rectified by the diode 162 and filtered bythe ca pacitors 160 and 168 whereupon conduction of the amplifiertransistor 153 is effected.

When the amplifier transistor 153 conducts, current supplied by thetransformer winding 163 flows through the DC motor 164, the amplifiertransistor 153, the gate circuit of the SCR 157, and the diode 161 backto the transformer winding 163. As a result of the current 191 andapproaches circuit ground level by way of the inactivated VHF or UHFtuners 179 or 181. Thus, rotation is continued until a following signalchannel contact 171 is attained by the rotatable arm 169.

Further, remote tracking of manual operation is effected in a mannersimilar to that previously explained with respect to the AC version of aremote control system. Briefly, a potential from the potential source139 is applied via contact 174 via a closed manual switch 173, therotatable arm 169 and resistor 199 to the cathode of diode 203 causingdiode 203 to be nonconductive and amplifier transistor 154 turned off.Upon closure of another one of the manually operable switches 173, theabove-mentioned potential path is interrupted causing diode 203 to beconductive through resistors 201 and 205 to ground which turns amplifiertransistor 154 on until the above-mentioned potential path isre-established by rotation of arm 169 to the closed switch 173.

Thus, there has been provided a unique remote control system having anenhanced control circuit. The system features both AC and DC operationalversions as well as circuitry for effecting tracking of manual tuning byremote tuning circuitry. Also, the improved control circuitry includes asustaining circuit whereby a given direction of rotational movement ismaintained until a desired signal channel is attained. Moreover, adisablement circuit insures disablement of circuitry for effectingopposite directional rotation until a desired amount of rotation in thegiven direction is attained.

While there has been shown and described what is at present consideredthe preferred embodiments of the invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing'from the invention as defined by the appendedclaims.

What is claimed is:

1. In a signal receiver having a plurality of signal channels, acontrolcircuit for a remote control system comprising:

a source of rotational direction signals and a potentialsource;bi-directional motor means;

first and second potential development means coupled to saidsignalsource and said motor means; disablement circuitmeans interconnectingsaid first and second potential development means for effectingdisablement of one of said first and second potential development meansupon enablement of the other of said potential development means; rotaryswitching means having a rotatable arm and a plurality signal channelcontacts each coupled by a channel indicating means to a varactor tunermeans, said arm mechanically coupled to said motor means, electricallycoupled to said potential source, and selectively coupled to one of saidplurality of signal channel contacts;

tracking means coupled to said rotary switching means and to saidpotential sustaining means to effect tracking of manual tunings by saidremote control system;

potential sustaining means coupled to said rotary switching means and tosaid first and second potential development means for effectingcontinued rotation of said motor means intermediate coupling of saidrotatable arm to one of said plurality of signal channel contacts; and

remote-manual switching means having first and second terminals coupledto said rotary switching means and a remote solenoid means coupled tosaid first and second potential development means for selectivelycoupling said first and second terminals to said potential source.

2. The control circuit of claim 1 wherein each one of said first andsecond potential development means includes signal detector means,amplifier means, and switching means coupled to said signal source andsaid bi-directional motor means.

3. The control circuit of claim 1 wherein said potential sustainingmeans includes a pair of unidirectional conduction devices coupled toone another and to said first and second potential development meanswith the junction therebetween coupled to said rotary switching means.

4. The control circuit of claim 1 wherein said rotary switching meansincludes a plurality of manually operable switches each coupled to asignal channel contact and in common to said remote-manual switchingmeans, said switches being mechanically interconnected to provideclosure of only one and opening of all remaining switches at any onetime.

5. In a signal receiver having a plurality of signal channels, a controlcircuit for a remote control system comprising:

a source of rotational direction signals;

a potential source;

bi-directional motor means including an AC motor having a pair ofwindings;

first and second potential development means coupled to said source ofrotational direction signals and to said motor means by way of saidwindings connected to a potential source;

disablement circuit means wherein each one of said first and secondpotential development means is coupled to the other by a first impedancewith a second impedance coupling said first impedance and one of saidfirst and second potential development means to a potential referencelevel;

rotary switching means having a rotatable arm and a plurality of signalchannel contacts with said rotatable arm mechanically coupled to said ACmotor and selectively coupled to one of said plurality of signal channelcontacts;

remote-manual switching means coupled to said potential source andselectively connected to said rtary switching means;

potential sustaining means coupled to said rotary switching means and tosaid first and second potential development means for efiectingapplication of a potential to one of said pair of windings and rotationof said AC motor in accordance with a signal from said source ofsustaining signals; and

tracking means in the form of a series connected resistor and diodecoupling said rotary switching means to said potential sustaining means.

6. The control circuit of claim 5 wherein each one of said first andsecond potential development means includes a detector means coupled tosaid source of rotational direction signals; an amplifier means coupledto said detector means and potential sustaining means, to said AC motormeans, and to the opposite one of said first and second potentialdevelopment means; and a switching means coupled intermediate saidamplifier means and a potential reference level and to the opposite oneof said first and second potential development means.

7. The control circuit of claim 5 wherein said remotemanual switchingmeans includes a solenoid means coupled to said first and secondpotential development means for selectively coupling said potentialsource to said rotary switching means in accordance with a signal fromsaid source of rotational direction signals.

8. The control circuit of claim 5 wherein said potential sustainingmeans includes an amplifier stage coupled to said rotary switching meansfor effecting amplification and inversion of a signal provided by saidrotary switching means.

9. The control circuit of claim 5 wherein said potential sustainingmeans includes a diode coupled to said rotary switching means foreffecting alteration in the potential applied to said first and secondpotential development means in accordance with the potential availablefrom said rotary switching means.

10. The control circuit of claim 5 wherein said rotary switching meansis coupled to VHF and UHF tuners of the varactor type.

11. The control circuit of claim 5 wherein said rotary switching meansincludes a plurality of signal channel contacts formed to provide bandswitching groups with each contact coupled to a channel indicatingmeans, to a manually operable switch means, and selectively coupled tosaid rotatable arm.

12. In a signal receiver having a plurality of signal channels, acontrol circuit for a remote control system comprising:

rotational direction signal sources;

a potential source;

bi-directional motor means including a transformer coupled to a powersource and having a winding in series connection with a DC motor;

first and second potential development means each coupled to arotational direction signal source and to said bi-directional motormeans;

disablement circuit means having a first capacitor coupled to circuitground and to a first resistor interconnecting said first and secondpotential development means and a second capacitor coupled to circuitground and to a second resistor interconnecting said first and secondpotential development means;

rotary switching means having a rotatable arm and a plurality of signalchannel contacts, said rotatable arm mechanically coupled to said DCmotor and selectively coupled to one of said signal channel contacts;

remote-manual switching means coupled to said potential source andselectively coupled to said rotary switching means;

potential sustaining means coupled to said rotary switching means and tosaid first and second potential development means for effectingcontinued directional rotation of said DC motor means intermediatecontact of said rotatable arm with said signal channel contacts; and

tracking means coupling said rotary switching means to the junction ofsaid potential sustaining means and said second potential developmentmeans whereby tracking of manual tuning by a remote tuning circuit iseffected.

13. The control circuit of claim 12 wherein said first and secondpotential development means each include a detector stage coupled to asignal source, an amplifier stage coupled to said detector stage by adiode, and a switching means in the form of a silicon controlledrectifier coupled to said DC motor means.

14. The control circuit of claim 12 wherein each one of said first andsecond potential development means includes a silicon controlledrectifier coupled to said DC motor means and to a potential referencelevel and a parallel coupled diode and capacitor shunting said siliconcontrolled rectifier.

15. The control circuit of claim 12 wherein said remote-manual switchingmeans includes a solenoid means coupled by diodes to said first and tosaid second potential development means.

16. The control circuit of claim 12 wherein said rotary switching meansincludes a plurality of parallel coupled and mechanically interconnectedsignal channel switches whereby closure of one of said switches insuresnon-closure of any other of the plurality of switches.

1. In a signal receiver having a plurality of signal channels, a controlcircuit for a remote control system comprising: a source of rotationaldirection signals and a potential source; bi-directional motor means;first and second potential development means coupled to said signalsource and said motor means; disablement circuit means interconnectingsaid first and second potential development means for effectingdisablement of one of said first and second potential development meansupon enablement of the other of said potential development means; rotaryswitching means having a rotatable arm and a plurality signal channelcontacts each coupled by a channel indicating means to a varactor tunermeans, said arm mechanically coupled to said motor means, electricallycoupled to said potential source, and selectively coupled to one of saidplurality of signal channel contacts; tracking means coupled to saidrotary switching meanS and to said potential sustaining means to effecttracking of manual tunings by said remote control system; potentialsustaining means coupled to said rotary switching means and to saidfirst and second potential development means for effecting continuedrotation of said motor means intermediate coupling of said rotatable armto one of said plurality of signal channel contacts; and remote-manualswitching means having first and second terminals coupled to said rotaryswitching means and a remote solenoid means coupled to said first andsecond potential development means for selectively coupling said firstand second terminals to said potential source.
 2. The control circuit ofclaim 1 wherein each one of said first and second potential developmentmeans includes signal detector means, amplifier means, and switchingmeans coupled to said signal source and said bi-directional motor means.3. The control circuit of claim 1 wherein said potential sustainingmeans includes a pair of unidirectional conduction devices coupled toone another and to said first and second potential development meanswith the junction therebetween coupled to said rotary switching means.4. The control circuit of claim 1 wherein said rotary switching meansincludes a plurality of manually operable switches each coupled to asignal channel contact and in common to said remote-manual switchingmeans, said switches being mechanically interconnected to provideclosure of only one and opening of all remaining switches at any onetime.
 5. In a signal receiver having a plurality of signal channels, acontrol circuit for a remote control system comprising: a source ofrotational direction signals; a potential source; bi-directional motormeans including an AC motor having a pair of windings; first and secondpotential development means coupled to said source of rotationaldirection signals and to said motor means by way of said windingsconnected to a potential source; disablement circuit means wherein eachone of said first and second potential development means is coupled tothe other by a first impedance with a second impedance coupling saidfirst impedance and one of said first and second potential developmentmeans to a potential reference level; rotary switching means having arotatable arm and a plurality of signal channel contacts with saidrotatable arm mechanically coupled to said AC motor and selectivelycoupled to one of said plurality of signal channel contacts;remote-manual switching means coupled to said potential source andselectively connected to said rotary switching means; potentialsustaining means coupled to said rotary switching means and to saidfirst and second potential development means for effecting applicationof a potential to one of said pair of windings and rotation of said ACmotor in accordance with a signal from said source of sustainingsignals; and tracking means in the form of a series connected resistorand diode coupling said rotary switching means to said potentialsustaining means.
 6. The control circuit of claim 5 wherein each one ofsaid first and second potential development means includes a detectormeans coupled to said source of rotational direction signals; anamplifier means coupled to said detector means and potential sustainingmeans, to said AC motor means, and to the opposite one of said first andsecond potential development means; and a switching means coupledintermediate said amplifier means and a potential reference level and tothe opposite one of said first and second potential development means.7. The control circuit of claim 5 wherein said remote-manual switchingmeans includes a solenoid means coupled to said first and secondpotential development means for selectively coupling said potentialsource to said rotary switching means in accordance with a signal fromsaid source of rotational direction signals.
 8. The control circuit ofclaim 5 wherein said potential sustainIng means includes an amplifierstage coupled to said rotary switching means for effecting amplificationand inversion of a signal provided by said rotary switching means. 9.The control circuit of claim 5 wherein said potential sustaining meansincludes a diode coupled to said rotary switching means for effectingalteration in the potential applied to said first and second potentialdevelopment means in accordance with the potential available from saidrotary switching means.
 10. The control circuit of claim 5 wherein saidrotary switching means is coupled to VHF and UHF tuners of the varactortype.
 11. The control circuit of claim 5 wherein said rotary switchingmeans includes a plurality of signal channel contacts formed to provideband switching groups with each contact coupled to a channel indicatingmeans, to a manually operable switch means, and selectively coupled tosaid rotatable arm.
 12. In a signal receiver having a plurality ofsignal channels, a control circuit for a remote control systemcomprising: rotational direction signal sources; a potential source;bi-directional motor means including a transformer coupled to a powersource and having a winding in series connection with a DC motor; firstand second potential development means each coupled to a rotationaldirection signal source and to said bi-directional motor means;disablement circuit means having a first capacitor coupled to circuitground and to a first resistor interconnecting said first and secondpotential development means and a second capacitor coupled to circuitground and to a second resistor interconnecting said first and secondpotential development means; rotary switching means having a rotatablearm and a plurality of signal channel contacts, said rotatable armmechanically coupled to said DC motor and selectively coupled to one ofsaid signal channel contacts; remote-manual switching means coupled tosaid potential source and selectively coupled to said rotary switchingmeans; potential sustaining means coupled to said rotary switching meansand to said first and second potential development means for effectingcontinued directional rotation of said DC motor means intermediatecontact of said rotatable arm with said signal channel contacts; andtracking means coupling said rotary switching means to the junction ofsaid potential sustaining means and said second potential developmentmeans whereby tracking of manual tuning by a remote tuning circuit iseffected.
 13. The control circuit of claim 12 wherein said first andsecond potential development means each include a detector stage coupledto a signal source, an amplifier stage coupled to said detector stage bya diode, and a switching means in the form of a silicon controlledrectifier coupled to said DC motor means.
 14. The control circuit ofclaim 12 wherein each one of said first and second potential developmentmeans includes a silicon controlled rectifier coupled to said DC motormeans and to a potential reference level and a parallel coupled diodeand capacitor shunting said silicon controlled rectifier.
 15. Thecontrol circuit of claim 12 wherein said remote-manual switching meansincludes a solenoid means coupled by diodes to said first and to saidsecond potential development means.
 16. The control circuit of claim 12wherein said rotary switching means includes a plurality of parallelcoupled and mechanically interconnected signal channel switches wherebyclosure of one of said switches insures non-closure of any other of theplurality of switches.